If you mean the Pressure Reducing Valve where the water line enters the house, then the answer is no, since there is no relationship between that valve and the water heater. A plumber that did that automatically, if the existing one was not defective, would either be overpriced compared to other companies or faulted for doing, and charging for, unnecessary work. but, if you mean the T&P valve on the water heater, then that valve should always be replaced.

: So, is it "standard" in the industry to replace the PRV when a company is installing a new hw heater?